SGP Cloud and Land Surface Interaction Campaign (CLASIC): Science and Implementation Plan

Miller, M. A.; Avissar, Roni; Berg, LK; Edgerton, SA; Jackson, T; Kustas, B.; Lamb, P.J.; McFarquhar, Greg M.; Min, Qilong; Schmid, Baptiste; Torn, M. S.; Turner, D. D.

doi:10.2172/948100

Cited by 6 publications

(6 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Cloud and LAnd‐Surface Interaction Campaign (CLASIC; Miller, ) was a three‐week continental campaign studying deep convection. It was carried out from 10 to 30 June 2007 over the US Department of Energy (DOE) Atmospheric Radiation Measurement Climate Research Facility at Southern Great Plains (ARM‐SGP) in Oklahoma, USA (36.61°N, 97.49°W).…”

Section: Model Comparisons To Observationsmentioning

confidence: 99%

Aerosol indirect effects on glaciated clouds. Part I: Model description

Kudzotsa

Phillips

Dobbie

et al. 2016

Quart J Royal Meteoro Soc

View full text Add to dashboard Cite

Various improvements were made to a state‐of‐the‐art aerosol–cloud model and comparison of the model results with observations from field campaigns was performed. The strength of this aerosol–cloud model is in its ability to explicitly resolve all the known modes of heterogeneous cloud droplet activation and ice crystal nucleation. The model links cloud particle activation with the aerosol loading and chemistry of seven different aerosol species. These improvements to the model resulted in more accurate prediction especially of droplet and ice crystal number concentrations in the upper troposphere and enabled the model to directly sift the aerosol indirect effects based on the chemistry and concentration of the aerosols. In addition, continental and maritime cases were simulated for the purpose of validating the aerosol–cloud model and for investigating the critical microphysical and dynamical mechanisms of aerosol indirect effects from anthropogenic solute and solid aerosols, focusing mainly on glaciated clouds. The simulations showed that increased solute aerosols reduced cloud particle sizes by about 5 μm and inhibited warm rain processes. Cloud fractions and their optical thicknesses were increased quite substantially in both cases. Although liquid mixing ratios were boosted, there was however a substantial reduction of ice mixing ratios in the upper troposphere owing to the increase in snow production aloft. These results are detailed in the subsequent parts of this study.

show abstract

Section: Model Comparisons To Observationsmentioning

confidence: 99%

Aerosol indirect effects on glaciated clouds. Part I: Model description

Kudzotsa

Phillips

Dobbie

et al. 2016

Quart J Royal Meteoro Soc

View full text Add to dashboard Cite

show abstract

“…[17] CHAPS was designed to study cloud-aerosol interactions in the vicinity of Oklahoma City, Oklahoma during June 2007 and was conducted in conjunction with the DOE Atmospheric Radiation Measurement (ARM) Cloud and Land Surface Interaction Campaign [Miller et al, 2007]. Two aircraft were deployed during CHAPS, the DOE G1 and the NASA Langley King Air B200.…”

Section: Field Study Descriptionmentioning

confidence: 99%

Modeling aerosols and their interactions with shallow cumuli during the 2007 CHAPS field study

et al. 2013

View full text Add to dashboard Cite

[1] The Weather Research and Forecasting model coupled with chemistry, using 2 km horizontal grid spacing, is used to simulate two important relationships between aerosols and clouds in the vicinity of Oklahoma City during the June 2007 Cumulus Humilis Aerosol Processing Study (CHAPS). First, the model reproduces the trends of higher nitrate volume fractions in cloud droplet residuals compared to interstitial nonactivated aerosols, as measured using an aerosol mass spectrometer. Comparing simulations with cloud chemistry turned on and off, we show that nitric acid vapor uptake by cloud droplets explains the higher nitrate content of cloud droplet residuals. Second, the model reasonably represents the observations of the first aerosol indirect effect where pollutants in the vicinity of Oklahoma City increase cloud droplet number concentrations and decrease the droplet effective radius. In addition, as documented using an offline optical code, simulated aerosol optical properties depend on several compensating effects including aerosol water content, size-resolved chemical composition, and refractory index of various particle chemical species. All of our four sensitivity test cases clearly show an increase in simulated absorption and a decrease in single scattering albedo within the Oklahoma City plume relative to conditions outside the plume. While previous studies have often focused on cloud-aerosol interactions in stratiform and deep convective clouds, this study highlights the ability of regional-scale models to represent some of the important aspects of cloud-aerosol interactions associated with fields of short-lived shallow cumuli.

show abstract

“…They also show that convective initiation is localized in regions of moisture convergence and high instability in the boundary layer. 1) that propagated over Oklahoma (OK) on 19 and 20 June 2007 during the Cloud and Land Surface Interaction Campaign (CLASIC; Miller et al 2007) that is illustrative of eastward-propagating rainfall systems. Carbone and Tuttle (2008) describe three dominant mechanisms of nocturnal rainfall in the SGP: 1) the eastward propagation of rainfall systems originating along the Continental Divide, 2) the nocturnal reversal of the mountain-plains circulations, and 3) moisture convergence and instability associated with the Great Plains low-level jet.…”

Section: Introductionmentioning

confidence: 99%

A Study of the Role of Daytime Land–Atmosphere Interactions on Nocturnal Convective Activity in the Southern Great Plains during CLASIC

Erlingis

Barros

2014

Journal of Hydrometeorology

View full text Add to dashboard Cite

This study examines whether and how land-atmosphere interactions can have an impact on nocturnal convection over the southern Great Plains (SGP) through numerical simulations of an intense nocturnal mesoscale convective system (MCS) on 19-20 June 2007 with the Weather Research and Forecasting (WRF) Model. High-resolution nested simulations were conducted using realistic and idealized land surfaces and two planetary boundary layer (PBL) parameterizations (PBLp): Yonsei University (YSU) and Mellor-Yamada-Janji c (MYJ). Differences in timing and amount of MCS precipitation among observations and model results were examined in the light of daytime land-atmosphere interactions, nocturnal prestorm environment, and cold pool strength. At the meso-g scale, land cover and soil type have as much of an effect on the simulated prestorm environment as the choice of PBLp: MYJ simulations exhibit strong sensitivity to changes in the land surface in contrast to negligible impact in the case of YSU. At the end of the afternoon, as the boundary layer collapses, a more homogeneous and deeper PBL (and stronger low-level shear) is evident for YSU as compared to MYJ when initial conditions and land surface properties are the same. At the meso-b scale, propagation speed is faster and organization (bow echo morphology) and cold pool strength are enhanced when nocturnal PBL heights are higher, and there is stronger low-level shear in the prestorm environment independent of the boundary layer parameterization for different land surface conditions. A comparison of one-and two-way nested MYJ results demonstrates how daytime land-atmosphere interactions modify the prestorm environment remotely through advection of low-level thermodynamic features. This remote feedback strongly impacts the MCS development phase as well as its spatial organization and propagation velocity and, consequently, nocturnal rainfall. These results indicate that synoptic-and meso-a-scale dynamics can play an important role in determining the spatial and temporal scales over which precipitation feedbacks of land-atmosphere interactions emerge regionally. Finally, this study demonstrates the high degree of uncertainty in defining the spatial and temporal scales of land-atmosphere interactions where and when organized convection is dominant.

show abstract

SGP Cloud and Land Surface Interaction Campaign (CLASIC): Science and Implementation Plan

Cited by 6 publications

References 12 publications

Aerosol indirect effects on glaciated clouds. Part I: Model description

Aerosol indirect effects on glaciated clouds. Part I: Model description

Modeling aerosols and their interactions with shallow cumuli during the 2007 CHAPS field study

A Study of the Role of Daytime Land–Atmosphere Interactions on Nocturnal Convective Activity in the Southern Great Plains during CLASIC

Contact Info

Product

Resources

About